Container systems may be used in many industries for storing, shipping and/or dispensing materials of any viscosity. For example, numerous manufacturing processes require the use of ultrapure liquids, such as acids, solvents, bases, photoresists, slurries, cleaning formulations, dopants, inorganic, organic, metalorganic and biological solutions, pharmaceuticals, and radioactive chemicals. Further many other industries use container systems for a variety of applications, for example the food industry, pharmaceutical industry, cosmetic industry, etc. Typically, a shipping and dispensing system will include a container of some kind, and/or a liner, a cap that may be used to seal and protect the contents of the storage system when the contents are not being dispensed, and a connector that may be used to dispense the contents from the container. The liner and or container may include a fitment that allows caps, connectors, or other coupling devices to be coupled with the container system. Some systems further include a dip tube or a dip tube assembly that may assist in dispensing the contents of the container.
Conventional dip tube assemblies may include a relatively long and slender tubular portion that may be generally cylindrically shaped having a given diameter and a given length, often depending on the intended use. The tubular portion may be configured for placement so as to extend into an interior cavity of a liner or other container. To assist in proper placement of the tubular portion, the tubular portion may be configured to cooperate with a coupler portion that is shaped and configured to substantially fit into, or adjacent to, the mouth of the liner or other container, such as by fitting into or adjacent to, or coupling with, a fitment portion of the liner or other container, so as to generally fixedly couple or connect the tubular portion with the liner or other container. The tubular portion and coupler portion may be, and often are, separate stand-alone parts. For example, the tubular portion may often be a standard tube and the coupler portion may be a particularly custom part designed to permit coupling between the standard tube and a custom dispense container. In this regard, the coupler portion may often be configured with a tubular receiving cavity designed to receive and accommodate liquid-tight insertion of the tubular portion and an exterior designed to substantially fit into, or adjacent to, the mouth or fitment portion of a particular model container or other custom container.
One such known dip tube assembly includes a coupler portion having a receiving cavity that has a generally circular opening and a diameter cross-section that slightly tapers or narrows moving further into the receiving cavity, away from the entrance thereof, so as to form a conical frustrum. The tubular portion of the dip tube assembly may be inserted into the opening of the conical frustrum shaped receiving cavity of the coupler in friction-fit or press-fit style, thereby snuggly holding the tubular portion in generally fixed attachment with the coupler portion for sealability.
Another known dip tube assembly includes a coupler portion that is configured at one end for insertion into a top end of the tubular portion, in somewhat reverse fashion to the previously described embodiment. In order to insert the end of the coupler portion into the top end of the tubular portion, the top end of the tubular portion is first heated on a mandrel to widen the opening, thereby permitting insertion of the coupler end. When cooled, the coupler and tubular portion are thereby coupled via interference fit. Other embodiments of dip tube assemblies are discussed in commonly-owned U.S. Prov. Appl. No. 61/831,202, titled “Dip Tube Assemblies and Methods of Manufacturing the Same,” filed Jun. 5, 2013.
In various embodiments of the dip tube assembly, sometimes when the dip tube assembly is seated in the fitment portion, a seal is created to isolate pressure or gas from the chemical stored in the container. However, if the user does not expel all of the chemical in the container, pressure can build and chemical can be undesirably forced out through the dip tube assembly. Accordingly, there is a need for dip tube assemblies that overcome the disadvantages of conventional dip tube assemblies in one or more ways. That is, there is a need for improved dip tube couplers that are capable of relieving pressure to prevent chemical from being unintentionally forced out through the dip tube assembly.